/* drivers/rtc/rtc-s3c.c * * Copyright (c) 2010 Samsung Electronics Co., Ltd. * http://www.samsung.com/ * * Copyright (c) 2004,2006 Simtec Electronics * Ben Dooks, <ben@simtec.co.uk> * http://armlinux.simtec.co.uk/ * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * S3C2410/S3C2440/S3C24XX Internal RTC Driver */ #include <linux/module.h> #include <linux/fs.h> #include <linux/string.h> #include <linux/init.h> #include <linux/platform_device.h> #include <linux/interrupt.h> #include <linux/rtc.h> #include <linux/bcd.h> #include <linux/clk.h> #include <linux/log2.h> #include <linux/slab.h> #include <linux/of.h> #include <linux/uaccess.h> #include <linux/io.h> #include <asm/irq.h> #include "rtc-s3c.h" enum s3c_cpu_type { TYPE_S3C2410, TYPE_S3C2416, TYPE_S3C2443, TYPE_S3C64XX, }; struct s3c_rtc_drv_data { int cpu_type; }; /* I have yet to find an S3C implementation with more than one * of these rtc blocks in */ static struct clk *rtc_clk; static void __iomem *s3c_rtc_base; static int s3c_rtc_alarmno = NO_IRQ; static int s3c_rtc_tickno = NO_IRQ; static enum s3c_cpu_type s3c_rtc_cpu_type; static DEFINE_SPINLOCK(s3c_rtc_pie_lock); static void s3c_rtc_alarm_clk_enable(bool enable) { static DEFINE_SPINLOCK(s3c_rtc_alarm_clk_lock); static bool alarm_clk_enabled; unsigned long irq_flags; spin_lock_irqsave(&s3c_rtc_alarm_clk_lock, irq_flags); if (enable) { if (!alarm_clk_enabled) { clk_enable(rtc_clk); alarm_clk_enabled = true; } } else { if (alarm_clk_enabled) { clk_disable(rtc_clk); alarm_clk_enabled = false; } } spin_unlock_irqrestore(&s3c_rtc_alarm_clk_lock, irq_flags); } /* IRQ Handlers */ static irqreturn_t s3c_rtc_alarmirq(int irq, void *id) { struct rtc_device *rdev = id; clk_enable(rtc_clk); rtc_update_irq(rdev, 1, RTC_AF | RTC_IRQF); if (s3c_rtc_cpu_type == TYPE_S3C64XX) writeb(S3C2410_INTP_ALM, s3c_rtc_base + S3C2410_INTP); clk_disable(rtc_clk); s3c_rtc_alarm_clk_enable(false); return IRQ_HANDLED; } static irqreturn_t s3c_rtc_tickirq(int irq, void *id) { struct rtc_device *rdev = id; clk_enable(rtc_clk); rtc_update_irq(rdev, 1, RTC_PF | RTC_IRQF); if (s3c_rtc_cpu_type == TYPE_S3C64XX) writeb(S3C2410_INTP_TIC, s3c_rtc_base + S3C2410_INTP); clk_disable(rtc_clk); return IRQ_HANDLED; } /* Update control registers */ static int s3c_rtc_setaie(struct device *dev, unsigned int enabled) { unsigned int tmp; dev_dbg(dev, "%s: aie=%d\n", __func__, enabled); clk_enable(rtc_clk); tmp = readb(s3c_rtc_base + S3C2410_RTCALM) & ~S3C2410_RTCALM_ALMEN; if (enabled) tmp |= S3C2410_RTCALM_ALMEN; writeb(tmp, s3c_rtc_base + S3C2410_RTCALM); clk_disable(rtc_clk); s3c_rtc_alarm_clk_enable(enabled); return 0; } static int s3c_rtc_setfreq(struct device *dev, int freq) { struct platform_device *pdev = to_platform_device(dev); struct rtc_device *rtc_dev = platform_get_drvdata(pdev); unsigned int tmp = 0; int val; if (!is_power_of_2(freq)) return -EINVAL; clk_enable(rtc_clk); spin_lock_irq(&s3c_rtc_pie_lock); if (s3c_rtc_cpu_type != TYPE_S3C64XX) { tmp = readb(s3c_rtc_base + S3C2410_TICNT); tmp &= S3C2410_TICNT_ENABLE; } val = (rtc_dev->max_user_freq / freq) - 1; if (s3c_rtc_cpu_type == TYPE_S3C2416 || s3c_rtc_cpu_type == TYPE_S3C2443) { tmp |= S3C2443_TICNT_PART(val); writel(S3C2443_TICNT1_PART(val), s3c_rtc_base + S3C2443_TICNT1); if (s3c_rtc_cpu_type == TYPE_S3C2416) writel(S3C2416_TICNT2_PART(val), s3c_rtc_base + S3C2416_TICNT2); } else { tmp |= val; } writel(tmp, s3c_rtc_base + S3C2410_TICNT); spin_unlock_irq(&s3c_rtc_pie_lock); clk_disable(rtc_clk); return 0; } /* Time read/write */ static int s3c_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm) { unsigned int have_retried = 0; void __iomem *base = s3c_rtc_base; clk_enable(rtc_clk); retry_get_time: rtc_tm->tm_min = readb(base + S3C2410_RTCMIN); rtc_tm->tm_hour = readb(base + S3C2410_RTCHOUR); rtc_tm->tm_mday = readb(base + S3C2410_RTCDATE); rtc_tm->tm_mon = readb(base + S3C2410_RTCMON); rtc_tm->tm_year = readb(base + S3C2410_RTCYEAR); rtc_tm->tm_sec = readb(base + S3C2410_RTCSEC); /* the only way to work out whether the system was mid-update * when we read it is to check the second counter, and if it * is zero, then we re-try the entire read */ if (rtc_tm->tm_sec == 0 && !have_retried) { have_retried = 1; goto retry_get_time; } rtc_tm->tm_sec = bcd2bin(rtc_tm->tm_sec); rtc_tm->tm_min = bcd2bin(rtc_tm->tm_min); rtc_tm->tm_hour = bcd2bin(rtc_tm->tm_hour); rtc_tm->tm_mday = bcd2bin(rtc_tm->tm_mday); rtc_tm->tm_mon = bcd2bin(rtc_tm->tm_mon); rtc_tm->tm_year = bcd2bin(rtc_tm->tm_year); rtc_tm->tm_year += 100; dev_dbg(dev, "read time %04d.%02d.%02d %02d:%02d:%02d\n", 1900 + rtc_tm->tm_year, rtc_tm->tm_mon, rtc_tm->tm_mday, rtc_tm->tm_hour, rtc_tm->tm_min, rtc_tm->tm_sec); rtc_tm->tm_mon -= 1; clk_disable(rtc_clk); return rtc_valid_tm(rtc_tm); } static int s3c_rtc_settime(struct device *dev, struct rtc_time *tm) { void __iomem *base = s3c_rtc_base; int year = tm->tm_year - 100; dev_dbg(dev, "set time %04d.%02d.%02d %02d:%02d:%02d\n", 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_hour, tm->tm_min, tm->tm_sec); /* we get around y2k by simply not supporting it */ if (year < 0 || year >= 100) { dev_err(dev, "rtc only supports 100 years\n"); return -EINVAL; } clk_enable(rtc_clk); writeb(bin2bcd(tm->tm_sec), base + S3C2410_RTCSEC); writeb(bin2bcd(tm->tm_min), base + S3C2410_RTCMIN); writeb(bin2bcd(tm->tm_hour), base + S3C2410_RTCHOUR); writeb(bin2bcd(tm->tm_mday), base + S3C2410_RTCDATE); writeb(bin2bcd(tm->tm_mon + 1), base + S3C2410_RTCMON); writeb(bin2bcd(year), base + S3C2410_RTCYEAR); clk_disable(rtc_clk); return 0; } static int s3c_rtc_getalarm(struct device *dev, struct rtc_wkalrm *alrm) { struct rtc_time *alm_tm = &alrm->time; void __iomem *base = s3c_rtc_base; unsigned int alm_en; clk_enable(rtc_clk); alm_tm->tm_sec = readb(base + S3C2410_ALMSEC); alm_tm->tm_min = readb(base + S3C2410_ALMMIN); alm_tm->tm_hour = readb(base + S3C2410_ALMHOUR); alm_tm->tm_mon = readb(base + S3C2410_ALMMON); alm_tm->tm_mday = readb(base + S3C2410_ALMDATE); alm_tm->tm_year = readb(base + S3C2410_ALMYEAR); alm_en = readb(base + S3C2410_RTCALM); alrm->enabled = (alm_en & S3C2410_RTCALM_ALMEN) ? 1 : 0; dev_dbg(dev, "read alarm %d, %04d.%02d.%02d %02d:%02d:%02d\n", alm_en, 1900 + alm_tm->tm_year, alm_tm->tm_mon, alm_tm->tm_mday, alm_tm->tm_hour, alm_tm->tm_min, alm_tm->tm_sec); /* decode the alarm enable field */ if (alm_en & S3C2410_RTCALM_SECEN) alm_tm->tm_sec = bcd2bin(alm_tm->tm_sec); else alm_tm->tm_sec = -1; if (alm_en & S3C2410_RTCALM_MINEN) alm_tm->tm_min = bcd2bin(alm_tm->tm_min); else alm_tm->tm_min = -1; if (alm_en & S3C2410_RTCALM_HOUREN) alm_tm->tm_hour = bcd2bin(alm_tm->tm_hour); else alm_tm->tm_hour = -1; if (alm_en & S3C2410_RTCALM_DAYEN) alm_tm->tm_mday = bcd2bin(alm_tm->tm_mday); else alm_tm->tm_mday = -1; if (alm_en & S3C2410_RTCALM_MONEN) { alm_tm->tm_mon = bcd2bin(alm_tm->tm_mon); alm_tm->tm_mon -= 1; } else { alm_tm->tm_mon = -1; } if (alm_en & S3C2410_RTCALM_YEAREN) alm_tm->tm_year = bcd2bin(alm_tm->tm_year); else alm_tm->tm_year = -1; clk_disable(rtc_clk); return 0; } static int s3c_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm) { struct rtc_time *tm = &alrm->time; void __iomem *base = s3c_rtc_base; unsigned int alrm_en; clk_enable(rtc_clk); dev_dbg(dev, "s3c_rtc_setalarm: %d, %04d.%02d.%02d %02d:%02d:%02d\n", alrm->enabled, 1900 + tm->tm_year, tm->tm_mon + 1, tm->tm_mday, tm->tm_hour, tm->tm_min, tm->tm_sec); alrm_en = readb(base + S3C2410_RTCALM) & S3C2410_RTCALM_ALMEN; writeb(0x00, base + S3C2410_RTCALM); if (tm->tm_sec < 60 && tm->tm_sec >= 0) { alrm_en |= S3C2410_RTCALM_SECEN; writeb(bin2bcd(tm->tm_sec), base + S3C2410_ALMSEC); } if (tm->tm_min < 60 && tm->tm_min >= 0) { alrm_en |= S3C2410_RTCALM_MINEN; writeb(bin2bcd(tm->tm_min), base + S3C2410_ALMMIN); } if (tm->tm_hour < 24 && tm->tm_hour >= 0) { alrm_en |= S3C2410_RTCALM_HOUREN; writeb(bin2bcd(tm->tm_hour), base + S3C2410_ALMHOUR); } dev_dbg(dev, "setting S3C2410_RTCALM to %08x\n", alrm_en); writeb(alrm_en, base + S3C2410_RTCALM); s3c_rtc_setaie(dev, alrm->enabled); clk_disable(rtc_clk); return 0; } static int s3c_rtc_proc(struct device *dev, struct seq_file *seq) { unsigned int ticnt; clk_enable(rtc_clk); if (s3c_rtc_cpu_type == TYPE_S3C64XX) { ticnt = readw(s3c_rtc_base + S3C2410_RTCCON); ticnt &= S3C64XX_RTCCON_TICEN; } else { ticnt = readb(s3c_rtc_base + S3C2410_TICNT); ticnt &= S3C2410_TICNT_ENABLE; } seq_printf(seq, "periodic_IRQ\t: %s\n", ticnt ? "yes" : "no"); clk_disable(rtc_clk); return 0; } static const struct rtc_class_ops s3c_rtcops = { .read_time = s3c_rtc_gettime, .set_time = s3c_rtc_settime, .read_alarm = s3c_rtc_getalarm, .set_alarm = s3c_rtc_setalarm, .proc = s3c_rtc_proc, .alarm_irq_enable = s3c_rtc_setaie, }; static void s3c_rtc_enable(struct platform_device *pdev, int en) { void __iomem *base = s3c_rtc_base; unsigned int tmp; if (s3c_rtc_base == NULL) return; clk_enable(rtc_clk); if (!en) { tmp = readw(base + S3C2410_RTCCON); if (s3c_rtc_cpu_type == TYPE_S3C64XX) tmp &= ~S3C64XX_RTCCON_TICEN; tmp &= ~S3C2410_RTCCON_RTCEN; writew(tmp, base + S3C2410_RTCCON); if (s3c_rtc_cpu_type != TYPE_S3C64XX) { tmp = readb(base + S3C2410_TICNT); tmp &= ~S3C2410_TICNT_ENABLE; writeb(tmp, base + S3C2410_TICNT); } } else { /* re-enable the device, and check it is ok */ if ((readw(base+S3C2410_RTCCON) & S3C2410_RTCCON_RTCEN) == 0) { dev_info(&pdev->dev, "rtc disabled, re-enabling\n"); tmp = readw(base + S3C2410_RTCCON); writew(tmp | S3C2410_RTCCON_RTCEN, base + S3C2410_RTCCON); } if ((readw(base + S3C2410_RTCCON) & S3C2410_RTCCON_CNTSEL)) { dev_info(&pdev->dev, "removing RTCCON_CNTSEL\n"); tmp = readw(base + S3C2410_RTCCON); writew(tmp & ~S3C2410_RTCCON_CNTSEL, base + S3C2410_RTCCON); } if ((readw(base + S3C2410_RTCCON) & S3C2410_RTCCON_CLKRST)) { dev_info(&pdev->dev, "removing RTCCON_CLKRST\n"); tmp = readw(base + S3C2410_RTCCON); writew(tmp & ~S3C2410_RTCCON_CLKRST, base + S3C2410_RTCCON); } } clk_disable(rtc_clk); } static int s3c_rtc_remove(struct platform_device *dev) { s3c_rtc_setaie(&dev->dev, 0); clk_unprepare(rtc_clk); rtc_clk = NULL; return 0; } static const struct of_device_id s3c_rtc_dt_match[]; static inline int s3c_rtc_get_driver_data(struct platform_device *pdev) { #ifdef CONFIG_OF struct s3c_rtc_drv_data *data; if (pdev->dev.of_node) { const struct of_device_id *match; match = of_match_node(s3c_rtc_dt_match, pdev->dev.of_node); data = (struct s3c_rtc_drv_data *) match->data; return data->cpu_type; } #endif return platform_get_device_id(pdev)->driver_data; } static int s3c_rtc_probe(struct platform_device *pdev) { struct rtc_device *rtc; struct rtc_time rtc_tm; struct resource *res; int ret; int tmp; dev_dbg(&pdev->dev, "%s: probe=%p\n", __func__, pdev); /* find the IRQs */ s3c_rtc_tickno = platform_get_irq(pdev, 1); if (s3c_rtc_tickno < 0) { dev_err(&pdev->dev, "no irq for rtc tick\n"); return s3c_rtc_tickno; } s3c_rtc_alarmno = platform_get_irq(pdev, 0); if (s3c_rtc_alarmno < 0) { dev_err(&pdev->dev, "no irq for alarm\n"); return s3c_rtc_alarmno; } dev_dbg(&pdev->dev, "s3c2410_rtc: tick irq %d, alarm irq %d\n", s3c_rtc_tickno, s3c_rtc_alarmno); /* get the memory region */ res = platform_get_resource(pdev, IORESOURCE_MEM, 0); s3c_rtc_base = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(s3c_rtc_base)) return PTR_ERR(s3c_rtc_base); rtc_clk = devm_clk_get(&pdev->dev, "rtc"); if (IS_ERR(rtc_clk)) { dev_err(&pdev->dev, "failed to find rtc clock source\n"); ret = PTR_ERR(rtc_clk); rtc_clk = NULL; return ret; } clk_prepare_enable(rtc_clk); /* check to see if everything is setup correctly */ s3c_rtc_enable(pdev, 1); dev_dbg(&pdev->dev, "s3c2410_rtc: RTCCON=%02x\n", readw(s3c_rtc_base + S3C2410_RTCCON)); device_init_wakeup(&pdev->dev, 1); /* register RTC and exit */ rtc = devm_rtc_device_register(&pdev->dev, "s3c", &s3c_rtcops, THIS_MODULE); if (IS_ERR(rtc)) { dev_err(&pdev->dev, "cannot attach rtc\n"); ret = PTR_ERR(rtc); goto err_nortc; } s3c_rtc_cpu_type = s3c_rtc_get_driver_data(pdev); /* Check RTC Time */ s3c_rtc_gettime(NULL, &rtc_tm); if (rtc_valid_tm(&rtc_tm)) { rtc_tm.tm_year = 100; rtc_tm.tm_mon = 0; rtc_tm.tm_mday = 1; rtc_tm.tm_hour = 0; rtc_tm.tm_min = 0; rtc_tm.tm_sec = 0; s3c_rtc_settime(NULL, &rtc_tm); dev_warn(&pdev->dev, "warning: invalid RTC value so initializing it\n"); } if (s3c_rtc_cpu_type != TYPE_S3C2410) rtc->max_user_freq = 32768; else rtc->max_user_freq = 128; if (s3c_rtc_cpu_type == TYPE_S3C2416 || s3c_rtc_cpu_type == TYPE_S3C2443) { tmp = readw(s3c_rtc_base + S3C2410_RTCCON); tmp |= S3C2443_RTCCON_TICSEL; writew(tmp, s3c_rtc_base + S3C2410_RTCCON); } platform_set_drvdata(pdev, rtc); s3c_rtc_setfreq(&pdev->dev, 1); ret = devm_request_irq(&pdev->dev, s3c_rtc_alarmno, s3c_rtc_alarmirq, 0, "s3c2410-rtc alarm", rtc); if (ret) { dev_err(&pdev->dev, "IRQ%d error %d\n", s3c_rtc_alarmno, ret); goto err_nortc; } ret = devm_request_irq(&pdev->dev, s3c_rtc_tickno, s3c_rtc_tickirq, 0, "s3c2410-rtc tick", rtc); if (ret) { dev_err(&pdev->dev, "IRQ%d error %d\n", s3c_rtc_tickno, ret); goto err_nortc; } clk_disable(rtc_clk); return 0; err_nortc: s3c_rtc_enable(pdev, 0); clk_disable_unprepare(rtc_clk); return ret; } #ifdef CONFIG_PM_SLEEP /* RTC Power management control */ static int ticnt_save, ticnt_en_save; static bool wake_en; static int s3c_rtc_suspend(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); clk_enable(rtc_clk); /* save TICNT for anyone using periodic interrupts */ if (s3c_rtc_cpu_type == TYPE_S3C64XX) { ticnt_en_save = readw(s3c_rtc_base + S3C2410_RTCCON); ticnt_en_save &= S3C64XX_RTCCON_TICEN; ticnt_save = readl(s3c_rtc_base + S3C2410_TICNT); } else { ticnt_save = readb(s3c_rtc_base + S3C2410_TICNT); } s3c_rtc_enable(pdev, 0); if (device_may_wakeup(dev) && !wake_en) { if (enable_irq_wake(s3c_rtc_alarmno) == 0) wake_en = true; else dev_err(dev, "enable_irq_wake failed\n"); } clk_disable(rtc_clk); return 0; } static int s3c_rtc_resume(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); unsigned int tmp; clk_enable(rtc_clk); s3c_rtc_enable(pdev, 1); if (s3c_rtc_cpu_type == TYPE_S3C64XX) { writel(ticnt_save, s3c_rtc_base + S3C2410_TICNT); if (ticnt_en_save) { tmp = readw(s3c_rtc_base + S3C2410_RTCCON); writew(tmp | ticnt_en_save, s3c_rtc_base + S3C2410_RTCCON); } } else { writeb(ticnt_save, s3c_rtc_base + S3C2410_TICNT); } if (device_may_wakeup(dev) && wake_en) { disable_irq_wake(s3c_rtc_alarmno); wake_en = false; } clk_disable(rtc_clk); return 0; } #endif static SIMPLE_DEV_PM_OPS(s3c_rtc_pm_ops, s3c_rtc_suspend, s3c_rtc_resume); #ifdef CONFIG_OF static struct s3c_rtc_drv_data s3c_rtc_drv_data_array[] = { [TYPE_S3C2410] = { TYPE_S3C2410 }, [TYPE_S3C2416] = { TYPE_S3C2416 }, [TYPE_S3C2443] = { TYPE_S3C2443 }, [TYPE_S3C64XX] = { TYPE_S3C64XX }, }; static const struct of_device_id s3c_rtc_dt_match[] = { { .compatible = "samsung,s3c2410-rtc", .data = &s3c_rtc_drv_data_array[TYPE_S3C2410], }, { .compatible = "samsung,s3c2416-rtc", .data = &s3c_rtc_drv_data_array[TYPE_S3C2416], }, { .compatible = "samsung,s3c2443-rtc", .data = &s3c_rtc_drv_data_array[TYPE_S3C2443], }, { .compatible = "samsung,s3c6410-rtc", .data = &s3c_rtc_drv_data_array[TYPE_S3C64XX], }, {}, }; MODULE_DEVICE_TABLE(of, s3c_rtc_dt_match); #endif static struct platform_device_id s3c_rtc_driver_ids[] = { { .name = "s3c2410-rtc", .driver_data = TYPE_S3C2410, }, { .name = "s3c2416-rtc", .driver_data = TYPE_S3C2416, }, { .name = "s3c2443-rtc", .driver_data = TYPE_S3C2443, }, { .name = "s3c64xx-rtc", .driver_data = TYPE_S3C64XX, }, { } }; MODULE_DEVICE_TABLE(platform, s3c_rtc_driver_ids); static struct platform_driver s3c_rtc_driver = { .probe = s3c_rtc_probe, .remove = s3c_rtc_remove, .id_table = s3c_rtc_driver_ids, .driver = { .name = "s3c-rtc", .owner = THIS_MODULE, .pm = &s3c_rtc_pm_ops, .of_match_table = of_match_ptr(s3c_rtc_dt_match), }, }; module_platform_driver(s3c_rtc_driver); MODULE_DESCRIPTION("Samsung S3C RTC Driver"); MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:s3c2410-rtc");